> However, the NATs generally employed by mobile data networks are pathological, such that it’s virtually impossible for two clients on a mobile data network to establish a direct connection with each-other.
This problem, and the entirety of the resulting "solution¹" and the engineering complexity that stems from it in the article, is completely solved by IPv6, because it renders NAT obsolete.
While I agree that IPv6 makes NAT obsolete, I, unfortunately, don't see NAT going away even after everyone is 100% on IPv6. Too many people/companies rely on NAT for "security" for it to completely die.
At worst, I see NAT being replaced with default-reject-unless-associated-with-an-existing-internally-initiated-connection border firewalls everywhere a sysadmin with half a clue works.
And that's what I would do (basic stateful inspection), but there are too many organizations (especially SMBs with little/no I.T. staff onboard) who will simply use NAT with IPv6 to get that same end result.
At least until we deplete all the ipv6 addresses. With some of the crazy applications (ways of doing things) being developed to service Kubernetes clusters on AWS, I can see this happening faster than the ipv4 depletion.
Given that there's enough addresses to assign around 1000000 addresses to every bacterial cell on the planet, you can safely expect that it will last longer than ipv4. It's not a matter of "oh, lets double it that should be big enough", the ipv6 space is around 18 orders of magnitude larger. Computers and our uses for them would have to change enormously for us to exhaust that. Not saying it won't ever happen, but it'll be a while.
This problem, and the entirety of the resulting "solution¹" and the engineering complexity that stems from it in the article, is completely solved by IPv6, because it renders NAT obsolete.
¹not that they had a choice.